[black_beast]

Hey everyone, first I’d like to say I’m asking for help because I’ve exhausted all research available to me and I’m at a loss at what to do next, short of replacing the transfer case


Background...


Purchased a 2009 328xi 6 speed manual for my girlfriend in July of last year, about 140k miles

On the test drive, I noticed a very very slight shudder in low rpms under anything more then moderate throttle. No shudder under light throttle. Now in hindsight I know that’s a sign of potential issues with the transfer case but this is my first awd BMW aside from my X5 and I didn’t know. It was very very subtle and the car was otherwise great and I couldn’t pass up this 6 speed e90 (we were looking for an XI for snowboarding)


Purchased in July of 2020, car ran great with zero issues until December. She got a flat rear tire, and replaced both back tires to keep it even. Same tire size but mismatched brands. The car came with sport package staggered 18’s, 225/40 and 255/35 rear


The very next day driving home, the trifecta lights pop on



So from reading online the general concensus for the trifecta is almost always the transfer case actuator motor. I swapped in a cheap amazon unit with no change.
So before throwing more money in at it blindly I took it to a German specialist auto repair shop who diagnosed it as the transfer case actuator. I wasn’t too surprised since I gambled buying a cheap one so I bought an Austrian made Rein unit from fcp euro. Again no change



Upon home diagnoses using a foxwell I discovered the brake fluid was a tad low and the battery was on it way out, filled up the brake fluid and replaced the battery with no change.

Speed sensors all read out correctly on the foxwell and don’t throw any codes so I don’t think they’re an issue.



So fast forward a couple weeks and I take it to another highly rated local BMW specialist repair shop for diagnosis, and long story short they say the transfer case is bad, however their reason for that is because they couldn’t get the calibration process for the VTG to initiate. That’s their only reason for making that proclamation that the transfer case is bad and gave me like a $4500 estimate to replace it


So that’s where I’m at right now. I don’t necessarily disagree that maybe the transfer case is indeed bad but it doesn’t make sense to me for several reasons so I have some questions that hopefully someone can answer




1. From what I’ve read online people say when your transfer case goes “you’ll know”. Can someone please explain what that means? We were in the middle of a 800 mile road trip with zero issues before the tire change. Absolutely zero issues, no weird noises, no clunks, howling, nothing

2. Is there is a concrete way to know that the transfer case does indeed need to be replaced?

3. Any ideas on what to do next? Maybe a dealer diagnosis?


There is a code for oil wear so I’m thinking as a last resort Hail Mary to try swapping the fluid and again trying to clear/calibrate and then at that point I wouldn’t know what else to do but to just swap the TC which I can probably do myself


Any ideas or tips would be greatly appreciated


This is my gfs first BMW that she bought for snowboard trips so this really sucks that she hasn’t even been able to use it for that on the first snow season that she’s owned it

Thanks for reading

[Sp749]

Same issue. Looking for insight.

[relative4]

Start with matching tires.